Faculty Bibliography

There are an estimated 10 000 monogenic diseases affecting tens of millions of individuals worldwide. The application of CRISPR/Cas genome editing tools to treat monogenic diseases is an emerging strategy with the potential to generate personalized treatment approaches for these patients. CRISPR/Cas-based systems are programmable and sequence-specific genome editing tools with the capacity to generate base pair resolution manipulations to DNA or RNA. The complexity of genomic insults resulting in heritable disease requires patient-specific genome editing strategies with consideration of DNA repair pathways, and CRISPR/Cas systems of different types, species, and those with additional enzymatic capacity and/or delivery methods. In this review we aim to discuss broad and multifaceted therapeutic applications of CRISPR/Cas gene editing systems including in harnessing of homology directed repair, non-homologous end joining, microhomology-mediated end joining, and base editing to permanently correct diverse monogenic diseases.

Sleep spindles are functionally important NREM sleep EEG oscillations which are generated in thalamocortical, corticothalamic and possibly cortico-cortical circuits. Previous hypotheses suggested that slow and fast spindles or spindles with various spatial extent may be generated in different circuits with various cortical laminar innervation patterns. We used NREM sleep EEG data recorded from four human epileptic patients undergoing presurgical electrophysiological monitoring with subdural electrocorticographic grids (ECoG) and implanted laminar microelectrodes penetrating the cortex (IME). The position of IMEs within cortical layers was confirmed using postsurgical histological reconstructions. Many spindles detected on the IME occurred only in one layer and were absent from the ECoG, but with increasing amplitude simultaneous detection in other layers and on the ECoG became more likely. ECoG spindles were in contrast usually accompanied by IME spindles. Neither IME nor ECoG spindle cortical profiles were strongly associated with sleep spindle frequency or globality. Multiple-unit and single-unit activity during spindles, however, was heterogeneous across spindle types, but also across layers and subjects. Our results indicate that extremely local spindles may occur in any cortical layer, but co-occurrence at other locations becomes likelier with increasing amplitude and the relatively large spindles detected on ECoG channels have a stereotypical laminar profile. We found no compelling evidence that different spindle types are associated with different laminar profiles, suggesting that they are generated in cortical and thalamic circuits with similar cortical innervation patterns. Local neuronal activity is a stronger candidate mechanism for driving functional differences between spindles subtypes.

Multiple neuro-ophthalmological manifestations have been described in association with COVID-19. These symptoms and signs may be the result of a range of pathophysiological mechanisms throughout the course from acute illness to recovery phase. Optic nerve dysfunction, eye movement abnormalities and visual field defects have been described.

OBJECTIVE:The combined spatiotemporal dynamics underlying sign language production remains largely unknown. To investigate these dynamics as compared to speech production we utilized intracranial electrocorticography during a battery of language tasks. METHODS:We report a unique case of direct cortical surface recordings obtained from a neurosurgical patient with intact hearing and bilingual in English and American Sign Language. We designed a battery of cognitive tasks to capture multiple modalities of language processing and production. RESULTS:We identified two spatially distinct cortical networks: ventral for speech and dorsal for sign production. Sign production recruited peri-rolandic, parietal and posterior temporal regions, while speech production recruited frontal, peri-sylvian and peri-rolandic regions. Electrical cortical stimulation confirmed this spatial segregation, identifying mouth areas for speech production and limb areas for sign production. The temporal dynamics revealed superior parietal cortex activity immediately before sign production, suggesting its role in planning and producing sign language. CONCLUSIONS:Our findings reveal a distinct network for sign language and detail the temporal propagation supporting sign production.

OBJECTIVE:To determine whether race is associated with the development of epilepsy following subdural hematoma (SDH), we identified adult survivors of SDH in a statewide administrative dataset and followed them for at least one year for revisits associated with epilepsy. METHODS:We performed a retrospective cohort study using claims data on all discharges from emergency departments (ED) and hospitals in California. We identified adults (age≥18) admitted from 2005-2011 with first-time, traumatic and non-traumatic SDH. We used validated diagnosis codes to identify a primary outcome of ED or inpatient revisit for epilepsy. We used multivariable Cox regression for survival analysis to identify demographic and medical risk factors for epilepsy. RESULTS:We identified 29,342 survivors of SDH (mean age 71.2 [SD 16.4], female sex 11,954 [41.1%]). 3,230 (11.0%) patients had revisits to ED's and/or hospitals with a diagnosis of epilepsy during the study period. Black patients (n=1,684 [5.7%]) had significantly increased risk compared to white patients (n=16,945 [57.7%]; HR 1.45, CI 1.28-1.64, p<0.001). Status epilepticus during the index SDH admission, though infrequent (n=94 [0.3%]), was associated with a nearly four-fold risk of epilepsy (HR 3.75, CI 2.80-5.03, p<0.001). Alcohol use, drug use, smoking, renal disease, as well as markers of injury severity (i.e., intubation, surgical intervention, length of stay, disposition other than home) were also associated with epilepsy (all p<0.05). CONCLUSIONS:We found an association between black race and ED and hospital revisits for epilepsy after SDH, establishing the presence of a racial subgroup that is particularly vulnerable to post-SDH epileptogenesis.

BACKGROUND:There is a paucity of data in the literature specific to men with epilepsy on anti-seizure medication (ASM). The current study investigated the time to conception as well as the gestational and the neurodevelopmental outcomes of offspring of men with epilepsy on ASM compared to controls. Additionally, the prevalence of psychiatric comorbidities, and measures of sexual performance in males with and without epilepsy were analyzed. METHODS:A total of 450 male patients with and without epilepsy at one hospital were provided questionnaires to determine demographic characteristics, epilepsy history, type of ASM at the time of conception, comorbidities and sexual health. Time to conception, fertility methods and offspring birth and developmental history born to males with and without epilepsy was recorded. Survey data was evaluated using Student's t-test for continuous variables and Fisher's exact test for categorical variables. Odds ratio (OR) were calculated to determine associations between the measured data. RESULTS:After matching for age, we analyzed a total of 110 males with epilepsy and 110 without epilepsy. In the epilepsy group there was a higher rate of psychiatric comorbidities such as major depressive disorder, general anxiety disorder, bipolar disorder, and suicidal ideation when compared to the control group (N = 110; OR 3.39; 95% IC: 1.87-6.13, p < 0.001). Males with epilepsy also had a higher frequency of low erection scores when compared to males without epilepsy (N = 70 with epilepsy, N = 76 without epilepsy; OR 3.67; 95% IC: 1.44-9.39, p = 0.005). Of the 110 men with a diagnosis of epilepsy, 17 conceived children while using ASMs (38 total children). A total of 18.42% of children born to fathers on ASMs experienced developmental delays compared to 2.63% of controls, however this result was not statistically significant (p = 0.056). In addition, we did not find that offspring had significantly different birth weights or gestational ages in men on ASM compared to controls (p > 0.05). CONCLUSIONS:The present study suggests that men with epilepsy have an increased incidence of psychiatric comorbidities, and altered sexual performance, specifically erectile dysfunction, when compared with men without epilepsy. There was no statistically significant difference in the rates of developmental disorders and birth characteristics among those men with epilepsy on ASM at the time of conception and controls.

We typically misestimate the dimensions of our body e.g., we perceive our fingers as shorter, and our torso as more elongated, than they actually are. It stands to reason that those metric biases may also extend to objects that we interact with, to facilitate attunement with the environment. To explore this hypothesis, we compared the metric representations of seven objects and the subjects' own hand using the Line Length Judgment task, in six experiments involving 152 healthy subjects. We evaluated the size estimation errors made for each target (hand or previously observed objects) by asking subjects to compare the vertical or horizontal dimension of a specific target against the length of a vertical or horizontal line. As expected, we showed that the hand is misperceived in its dimensions. Interestingly, we found that metric biases are also present for daily-life objects, such as a mobile phone and a coffee mug, and are not affected by familiarity with the objects. In contrast, objects that are less likely to be manipulated, either because they are potentially harmful or disgusting, were differently represented. Furthermore, the propensity to interact with an object, rated by an independent sample of subjects, best predicted the pattern of metric biases associated with that object. Taken together, these findings support the hypothesis that biases affecting the hand representation extend to objects that elicit action-oriented behavior, highlighting the importance of studying the body as integrated and active in the environment.